The user you replied to was talking about UK, not Europe.
Even if you take the European Union alone and ignore all the other European countries, the EU only legislates over a subset of things for member countries.
AFAIK, not even that. This topic came up in relation to Hungary (before Orban was gone). What I understood from the discussion is that a country can only be punished by not giving them EU funds, etc.
As opposed to what? Armed invasion?
1. https://news.ycombinator.com/item?id=48423657
I mentioned that Europe is a lot more than the EU, and even within the EU member countries diverge.
2. https://news.ycombinator.com/item?id=48423908
trumpdong then makes a comment that I interpret as saying the EU doesn't have a lot of power over member states, and saying that the worst which could happen to one of them is to be kicked out of the EU.
3. https://news.ycombinator.com/item?id=48424244
Slightly shocked by the idea that the EU should be doing something worse than expelling a member for not following the Union's rules, I use a _reductio ad absurdum_ and ask if they thought the EU should be harder and actually perform an armed invasion of a member state that didn't follow them.
4. https://news.ycombinator.com/item?id=48425100
To my shock, trumpdong literally says "yes".
5. https://news.ycombinator.com/item?id=48425487
I, due to the shock described above, decide to question again in more words if that's actually what they mean.
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Hopefully that responds your question. I see no straw man, but if you still do, please present it.
"ask if they thought the EU should be harder and actually perform an armed invasion of a member state that didn't follow them."
You asked this:
"> the worst they can do is kick them out of the EU
As opposed to what? Armed invasion?"
Where trumpdong reploed with a affirmative "yes". So the worst they can do is kick someone out. No one demanded the EU should do armed invasion.
I don't know why you're taking their pain.